Manufacture
The objective of WP 3 is to develop, document and demonstrate methodologies that enables standard RM systems to be used in industrial production of a selected set of products. Using tools developed and experiences gained in previous work packages, components of the project focus will be produced on RM systems, which must be adapted or reconfigured to handle the different types of internal structures. Parameters to be taken into account include materials (powder, composites, and infiltrants) and processing (process parameters, printing strategies and support strategies). Together with WPs 1 and 2 this WP will result in better a quality of finished parts, reduced scrap rate and a shorter lead time. The Work Package is divided in six major sub-WPs, each of which takes the project one step closer to these objectives:
Validation toolbox
RM technologies have many different capabilities to produce complex geometries: support structures required or not, accuracy, surface quality, internal structures complexity limitation, porosity ability, excess powder removal, material properties, building speed, maximum dimensions, availability of internal file format for the layers,...
Rules for lightweight parts
Lightweight internal structures are typically complex geometries impossible to produce with conventional techniques like CNC. RM processes bring efficient solutions to build such complex parts but several problems still have to be overcome. The size of the file becomes huge and may drastically slow down the building process. The removal of excess powder is also an important issue.
Rules for parts with internal channels
Parts with internal channels are also very difficult or impossible to build with conventional techniques, especially if the channels are long and tortuous, which is the case for complex hydraulics components. The size of the file may be huge only in the case of numerous and long channels. The removal of excess powder is here a very important issue and shows fully different situations with direct and indirect RM techniques.
Rules for porous parts
Porous parts are typically complex geometries produced by the RM process itself and not only by the 3D CAD file. A combination of process porosity and additional holes is possible with the purpose of enlarging the range of void zones in filters or to producing graded porosity using local variations.
Infiltration and sintering
Post machining is clearly required with near net shape manufacturing techniques but this will be performed in WP5. The steps involved here are only infiltration (for task 3.3) and post sintering (for task 3.4) required to enhance mechanical and thermal properties.
Process quality
Now the metal RM processes become mature enough to produce accurate parts with complex details and good mechanical and thermal properties. But are they able so far to produce short series of metal parts with a satisfactory reliability and stability? The WP will define some quality management tools for this matter.